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    <title>ShellCheck: SC2296 – Parameter expansions can't start with `{`. Double check syntax.</title>
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    <h1>SC2296 – ShellCheck Wiki</h1>
    <a href="https://github.com/koalaman/shellcheck/wiki/SC2296">See this page on GitHub</a>
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    <h2
id="parameter-expansions-cant-start-with--double-check-syntax">Parameter
expansions can't start with <code>{</code>. Double check syntax.</h2>
<p>(or any other character)</p>
<h3 id="problematic-code">Problematic code:</h3>
<div class="sourceCode" id="cb1"><pre class="sourceCode sh"><code class="sourceCode bash"><span id="cb1-1"><a href="SC2296.html#cb1-1" aria-hidden="true" tabindex="-1"></a><span class="bu">echo</span> <span class="st">&quot;Hello </span><span class="va">${</span><span class="er">{name</span><span class="va">}</span><span class="st">&quot;</span></span></code></pre></div>
<h3 id="correct-code">Correct code:</h3>
<div class="sourceCode" id="cb2"><pre class="sourceCode sh"><code class="sourceCode bash"><span id="cb2-1"><a href="SC2296.html#cb2-1" aria-hidden="true" tabindex="-1"></a><span class="bu">echo</span> <span class="st">&quot;Hello </span><span class="va">${name}</span><span class="st">&quot;</span></span></code></pre></div>
<h3 id="rationale">Rationale:</h3>
<p>ShellCheck found a parameter expansion <code>${something}</code> that
starts with an invalid character. In the example, this was caused by
accidentally duplicating the <code>{</code> in
<code>${{name}</code>.</p>
<p>Double check the syntax of what you're trying to do.</p>
<h3 id="exceptions">Exceptions:</h3>
<p>Some Zsh specific parameter expansions like <code>${(q)value}</code>
trigger this warning, but ShellCheck does not support Zsh.</p>
<p>If this warning triggers in code that works on Bash, Ksh, Dash or Sh,
please <a
href="https://github.com/koalaman/shellcheck/issues/new">submit a
bug</a>.</p>
<h3 id="related-resources">Related resources:</h3>
<ul>
<li>Help by adding links to BashFAQ, StackOverflow, man pages, POSIX,
etc!</li>
</ul>
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    <p style='font-size: 80%'><a href="../index.html">ShellCheck</a> is a static analysis tool for shell scripts. This page is part of its documentation.</p>
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